Fri·Oct 18, 2024Friday·October 18, 2024

1. 01*

   General Mass treatment for Z boson production in association with a heavy quark at hadron colliders

   Marco Guzzi🇺🇸 · Pavel Nadolsky🇺🇸 · Laura Reina🇺🇸 · Doreen Wackeroth🇺🇸 · Keping Xie🇺🇸

   We present the application of the ACOT and S-ACOT general mass variable flavor number schemes to proton-proton collisions with particular attention to the production of final states with at least one heavy quark. Subtraction and residual heavy-quark parton distribution functions are introduced to facilitate the implementation of this scheme at higher orders in perturbative QCD. The calculation of Z-boson hadronic production with at least one $b$ jet beyond the lowest order in QCD is considered for illustration purposes.

   hep-phEPJ Web Conf.(2024)·0 citations
2. 02*

   Sketching pion and proton mass distributions

   Xiaobin Wang🇨🇳 · Zanbin Xing🇨🇳 · Lei Chang🇨🇳 · Minghui Ding🇨🇳 · Khépani Raya🇪🇸 · Craig D. Roberts🇨🇳

   A light-front holographic model is used to illustrate an algebraic scheme for constructing a representation of a hadron's zero-skewness generalised parton distribution (GPD) from its valence-quark distribution function (DF) and electromagnetic form factor, $F_H$, without reference to deeply virtual Compton scattering data. The hadron's mass distribution gravitational form factor, $A_H$, calculated from this GPD is harder than $F_H$; and, for each hadron, the associated mass-density profile is more compact than the analogous charge profile, with each pion near-core density being larger than that of its proton partner. These features are independent of the scheme employed.

   hep-phhep-exhep-latnucl-ex+1PLB(2025)·13 citations
3. 03*

   Triple gauge coupling analysis using boosted $W$'s and $Z$'s

   O. J. P. Éboli🇧🇷 · Tathagata Ghosh🇮🇳 · Matheus Martines🇧🇷 · Sujay Shil🇧🇷

   We analyze the Large Hadron Collider potential to study triple couplings of the electroweak gauge bosons using their boosted hadronic decays. Deviations from Standard Model predictions spoil cancelations present in the Standard Model leading to the growth of the electroweak diboson production cross section at high center-of-mass energies. In this kinematical limit, $W$'s and $Z$'s are highly boosted, and consequently, their hadronic decays give rise to fat jets. Here, we show that the study of boosted hadronically decaying $W$ and $Z$ leads to limits on triple gauge couplings that are comparable to the ones originating from the leptonic decay channels.

   hep-phhep-exEPJC(2025)·0 citations
4. 04*

   Detectability of accretion-induced bosenovae in the Milky Way

   Dennis Maseizik🇩🇪 · Joshua Eby🇸🇪 · Hyeonseok Seong🇩🇪 · Günter Sigl🇩🇪

   We estimate collapse rates of axion stars in our galaxy based on the axion minicluster mass function of the Milky Way dark matter halo. We consider axion-like particles with different temperature evolution of the axion mass, including the QCD axion with $m_a=50\mu$eV. Combining estimates for the present-day axion star mass function from our previous work with the axion star accretion model predicted by self-similar growth, we can infer the expected number of bosenovae occurring within the Milky Way. Our estimates suggest that for an observation time of $t_{\mathrm{obs}}=1$yr, the majority of the up to $\sim 10^{13}$ bosenovae per galaxy occur in the densest miniclusters with initial overdensity parameter $\Phi \lesssim 10^4$. We discuss the detectability of such recurring axion bursts within our galactic vicinity and find that, for models with derivative couplings including axion-fermion interactions, potential broadband axion DM experiments can probe a large range of ALP masses $m_a\lesssim 10^{-6}$eV and with moderate improvements even the QCD axion case. For axions with non-derivative-type interactions like the axion-photon coupling, our analysis suggests that optimistic predictions with order-one dark matter abundance of axion stars $f_{\star }\sim 1$ can be probed by dedicated burst searches.

   hep-phPRD(2025)·6 citations
5. 05*

   The Theoretical Study of ${\Sigma }^{+}p\to \Lambda a_0^{+}p$ Reaction

   Yan Dai🇨🇳 · Aojia Xu🇨🇳 · Gang Li🇨🇳 · Mao Song🇨🇳 · Xuan Luo🇨🇳

   We conducted a theoretical study on the process ${\Sigma }^{+}p\to \Lambda a_0^{+}p$ based on an effective Lagrangian approach. This model encompasses the excitation of intermediate states leading to the production of $\Delta (1920)$ through ${\pi }^{+}$ and $K^{+}$ meson exchanges between the initial ${\Sigma }^{+}$ baryon and the initial proton $p$, as well as the generation of $\Delta (1940)$ via ${\pi }^{+}$ and ${\rho }^{+}$ meson exchanges. We provide predictions for the total and differential cross sections and discuss the potential impacts of cutoff parameters, off-shell effects, and branching ratios on the ${\Delta }^{\ast }\to a_{0}p$ decay. Given the dominance of $\Delta (1940)$ in the region close to the reaction threshold, this reaction is considered an ideal platform for deeply exploring the unique properties of the $\Delta (1940)$ resonance. Through this approach, we can gain a more precise understanding of the intrinsic characteristics of this particle.

   hep-phnucl-thInt.J.Theor.Phys.(2025)·0 citations
6. 06*

   Twist-3 contribution in the Drell-Yan process with tensor-polarized deuteron

   Si-Yi Qiao🇨🇳 · Qin-Tao Song🇨🇳

   The tensor-polarized structures of the deuteron can be probed through the proton-deuteron Drell-Yan process, where the proton is unpolarized and the deuteron is tensor polarized. This measurement will be conducted at Fermilab in the near future. In this reaction, the twist-3 contribution is not negligible compared to the twist-2 contribution due to the limited invariant mass of the dilepton pair. We calculate the twist-3 contribution for the Drell-Yan cross section with a tensor-polarized deuteron target, preserving the U(1)-gauge invariance of the hadronic tensor. The cross sections and weighted cross sections are expressed in terms of the tensor-polarized parton distribution functions (PDFs), thus one can extract the PDFs $f_{1LL}$, $f_{LT}$, and $f_{1LT}^{(1)}$ from the experimental measurements of Drell-Yan process. Our study should be helpful to solve the puzzle in the tensor-polarized structures of the deuteron.

   hep-phhep-exnucl-exnucl-thPRD(2025)·4 citations
7. 07*

   Heavy-light quark systems from the QCD instanton vacuum: $N_f=1$ light flavor case

   Ki-Hoon Hong🇰🇷 · Hyun-Chul Kim🇰🇷 · M. M. Musakhanov🇺🇿 · N. Rakhimov🇰🇷

   We investigate heavy-light quark systems within the framework of the QCD instanton vacuum, focusing on the $N_f=1$ light flavor case. We derive an effective heavy-light quark interaction from the low-energy QCD partition function and construct a heavy-meson effective Lagrangian. The physical residual mass of heavy mesons, $\Lambda$, is determined by employing compositeness and normalization conditions. We calculate the masses of $D$ and $B$ mesons and their weak decay constants to the leading order and next-to-leading order in the $1/m_Q$ expansion. The current results for $f_D$ and $f_B$ are in good agreement with recent lattice QCD data and PDG average values.

   hep-phPRD(2024)·3 citations
8. 08*

   Confined but chirally and chiral spin symmetric hot matter

   L. Ya. Glozman🇦🇹 · A. V. Nefediev🇩🇪 · R. F. Wagenbrunn🇦🇹

   We investigate properties of the quark--antiquark mesons at zero and finite temperature in the framework of a solvable chirally symmetric quark model with linear confining potential. The interquark interaction in the model is reminiscent of that derived in Coulomb gauge QCD, with the string tension being the only model parameter. We demonstrate that while the confining interaction induces spontaneous breaking of chiral symmetry at T=0, chiral symmetry gets restored at a temperature Tch ~ 90 MeV for the string tension fixed to provide the phenomenological value of the quark condensate. This temperature is similar to Tch ~ 130 MeV observed on the lattice in the chiral limit for N_c=3. The physical mechanism responsible for the chiral symmetry restoration in the confining regime is Pauli blocking of the quark levels, required for the existence of a nonvanishing quark condensate, by the thermal excitations of the quarks and antiquarks. Thus, above the chiral restoration temperature, the meson-like states are chirally symmetric and approximately chiral spin symmetric. A crucial property of the confined meson-like light-light states above Tch is their size that exceeds drastically that in the chirally broken phase below Tch, in contrast to the heavy-heavy mesons that nearly preserve their size irrespective of the temperature. This property is a result of Pauli blocking of the quark and antiquark levels with small momenta. Furthermore, the root-mean-square radius of the states with J=0,1 diverges in the chiral limit. This unexpected property must be a key to understanding unusual features of the hot QCD matter as observed at RHIC and LHC. Consequently, the confining but chirally symmetric matter above Tch can be considered as a dense system of very large and strongly overlapping meson-like states (``strings'').

   hep-phhep-exhep-lathep-th+1EPJC(2025)·7 citations
9. 09*

   Precision tests of third-generation four-quark operators: one- and two-loop matching

   Ulrich Haisch🇩🇪 · Luc Schnell🇩🇪

   We calculate the one- and two-loop matching corrections in the Standard Model effective field theory (SMEFT) that impact electroweak precision measurements and flavour physics observables, focusing on the contributions of third-generation four-quark operators. Our results provide a crucial ingredient for a model-independent analysis of constraints on beyond the Standard Model physics that primarily affects the sector of third-generation four-quark operators. Concise analytic expressions are provided for all considered precision observables, which should facilitate their inclusion into global SMEFT analyses.

   hep-phhep-exJHEP(2025)·24 citations
10. 10*

    Problems of dark atom cosmology

    V. A. Beylin🇫🇷 · M. Yu. Khlopov🇫🇷 · D. O. Sopin🇷🇺

    The dark atoms $XHe$ are the composite Thomson like atomic dark matter candidates. We address two cosmological problems of this model. The excess of new superheavy particles with even negative charge $X^{-2n}$ over the corresponding antiparticles is balanced by sphaleron transitions with baryon asymmetry and the mass range of $X$ particles should be specified at which this excess can provide dominance of dark atoms in the dark matter density. The other problem is possible capture of light nuclei by dark atoms, which can lead to formation of anomalous isotopes. The possibility of formation of multi dark atom systems at the nucleosynthesis stage is also studied. We approach these open questions of dark atom cosmology in the present work.

    hep-ph1 citation
11. 11*

    Heavy-light Pseudoscalar Mesons: Light-Front Wave Functions and Generalized Parton Distributions

    B. Almeida-Zamora🇲🇽 · J.J. Cobos-Martínez🇲🇽 · A. Bashir🇲🇽 · K. Raya🇪🇸 · J. Rodríguez-Quintero🇪🇸 · J. Segovia🇪🇸

    The internal structure of the lowest-lying pseudo-scalar mesons with heavy-light quark content is thoroughly studied using an algebraic model that has been successfully applied to similar physical observables of pseudoscalar and vector mesons with hidden-flavor quark content, ranging from light to heavy quark sectors. This model is based on constructing simple and evidence-based ansätze for the mesons' Bethe-Salpeter amplitude (BSA) and quark propagator, allowing the Bethe-Salpeter wave function (BSWF) to be computed algebraically. Its projection onto the light front yields the corresponding light-front wave function (LFWF), which provides easy access to the valence-quark Parton Distribution Amplitude (PDA) by integrating over the transverse momentum squared. We leverage our current knowledge of the PDAs of the lowest-lying pseudo-scalar heavy-light mesons to compute their Generalized Parton Distributions (GPDs) via the overlap representation of the LFWFs. From this three-dimensional information, various limits and projections allow us to deduce the related Parton Distribution Functions (PDFs), Electromagnetic Form Factors (EFFs), and Impact Parameter Space GPDs (IPS-GPDs). Whenever possible, we make explicit comparisons with available experimental results and previous theoretical predictions.

    hep-phhep-exhep-latnucl-ex+1PoS(2025)·1 citation
12. 12*

    Reply to Comment on "Neutrino oscillations originate from virtual excitation of Z bosons" and "Neutrinos produced from $\beta$ decays of neutrons cannot be in coherent superpositions of different mass eigenstates"

    Shi-Biao Zheng🇨🇳

    In this reply, I point out that the comment by Cline (arXiv:2410.05826) on my manuscripts (arXiv:2407.00954 and arXiv:2410.03133) has overlooked the critical fact that the quantum entanglement between the neutrino's mass and other degrees of freedom would destroy the quantum coherence between the mass eigenstates.

    hep-phquant-ph0 citations
13. 13*

    Proton internal pressure from deeply virtual Compton scattering on collider kinematics

    Hervé Dutrieux🇺🇸 · Thibaud Meisgny🇫🇷 · Cédric Mezrag🇫🇷 · Hervé Moutarde🇫🇷

    The unique experimental connection to the QCD energy-momentum tensor offered by generalised parton distributions has been strongly highlighted in the past few years with attempts to extract the pressure and shear forces distributions within the nucleon. If, in principle, this can be performed in a model independent way from experimental data, in practice, the current limited precision and kinematic coverage make such an extraction very challenging. Moreover, the limitation to a leading-order description in the strong coupling of the data has provided only an indirect and weakly sensitive access to gluon degrees of freedoms, solely through their mixing to quarks via evolution. In this paper we address this issue by pro viding a next-to-leading order formalism allowing a reanalysis of global fits with genuine gluonic degrees of freedom. In addition, we provide an estimate of the reduction in uncertainty that could stem from the extended kinematic range relevant for the future Electron Ion Collider. Finally, we stress the connection between the analysis of the dispersion relation in terms of generalised parton distributions and the deconvolution problem.

    hep-phnucl-thEPJC(2025)·13 citations
14. 14*

    Magnetic moments of ${\frac{1}{2}}^{-}$ baryon resonances in hot and dense strange hadronic matter

    Abhinaba Upadhyay🇮🇳 · Arvind Kumar🇮🇳 · Harleen Dahiya🇮🇳 · Suneel Dutt🇮🇳

    This work primarily focusses on determining the magnetic moments of ${\frac{1}{2}}^{-}$ baryon resonances in the presence of hot and dense hadronic matter. In the chiral $SU(3)$ quark mean field model approach, we have essentially accounted for the effects on in-medium scalar meson fields to investigate the impact of high densities on the in-medium baryon masses and their constituent quarks. In light of chiral constituent quark model $\chi$CQM, we have calculated the magnetic moments of ${\frac{1}{2}}^{-}$ baryon resonances and scrutinized the effects due to its internal constituents: the valence quarks, sea quarks and the orbital moment of sea quarks. Furthermore, we have investigated the effective baryonic magnetic moments for the finite magnitudes of isospin asymmetry and strangeness fraction.

    hep-phnucl-thPTEP(2025)·0 citations
15. 15*

    Probing Type-I 2HDM light Higgs in the top-pair-associated diphoton channel

    Yabo Dong🇨🇳 · Kun Wang🇨🇳 · Jingya Zhu🇨🇳

    Motivated by the possible 95 GeV diphoton excess, we investigate the capability of the Type-I Two-Higgs-Doublet Model (2HDM-I) to explain this signal under current theoretical and experimental constraints. Using full Monte Carlo (MC) simulations for the process of $pp\to t(\to W^{+}b)\bar{t}(\to W^{-}\bar{b})h(\to \gamma \gamma )$, we evaluate the discovery potential of a 95 GeV Higgs boson at future colliders. Direct Higgs searches strongly constrain the parameter $\alpha$, excluding the region with $\alpha \lesssim 0.95$. Monte Carlo results indicate that a minimum cross section of 0.3 fb is required to achieve a $5\sigma$ signal statistical significance at the HL-LHC with $L=3{\mathrm{ab}}^{-1}$. For the same luminosity, HE-LHC and FCC-hh require 0.67 fb and 2.36 fb, respectively. At the 14 TeV HL-LHC with an integrated luminosity of $3{\mathrm{ab}}^{-1}$, parameter regions with $\sin (\beta -\alpha )\gtrsim 0.4$ and $\sin (\beta -\alpha )\gtrsim 0.25$ can be probed at the $5\sigma$ and $2\sigma$ significance levels, respectively. At the 27 TeV HE-LHC with $L=10{\mathrm{ab}}^{-1}$, the sensitivity improves to $\sin (\beta -\alpha )\gtrsim 0.25$ ($5\sigma$) and $\gtrsim 0.15$ ($2\sigma$). For the 100 TeV FCC-hh with $L=30{\mathrm{ab}}^{-1}$, even regions with $\sin (\beta -\alpha )\gtrsim 0.1$ or $\sin (\beta -\alpha )\lesssim -0.05$ can be covered at the $5\sigma$ level. Parameter regions near $\sin (\beta -\alpha )\approx 0$ remain challenging to probe in the diphoton channel, even with increased energy or luminosity.

    hep-phhep-exPRD(2025)·8 citations
16. 16*

    Neutralino dark matter in the extension of MSSM with two triplets and singlet

    Zhong-Jun Yang🇨🇳 · Jin-Lei Yang🇨🇳 · Shu-Min Zhao🇨🇳 · Xing-Gang Wu🇨🇳 · Tai-Fu Feng🇨🇳

    In an extension of MSSM with two triplets and a singlet, called the TNMSSM, there are seven neutralinos which can enrich the study of cold dark matter if one expects that the weakly interacting massive particle (WIMP) is responsible for the observation of Planck satellite. Such a model, compared to the MSSM, can naturally offer a solution to the $\mu$ problem, and its lightest neutralino, which is bino-like, can also provide a correct relic density by using the coannihilation mechanism due to the newly added triplinos. Taking into account the related experimental measurements, such as the bound on the SM-like Higgs mass, the $B$ meson rare decays, the anomalous magnetic moment of the muon $a_{\mu }$, the Large Hadron Collider (LHC) measurements and the latest dark matter direct detection experiment LUX-ZEPLIN (LZ), the TNMSSM parameter space can be strictly limited. In respect to all the constraints mentioned above, we find that a bino-like neutralino with a mass in the region $[100,450]\mathrm{GeV}$ can successfully account for the correct dark matter relic density. Additionally, most of the viable parameter space can be tested in the near future experiments such as the Xenon-nT experiment or LHC.

    hep-phEPJC(2024)·5 citations
17. 17*

    The Affleck-Dine Curvaton

    Aurora Ireland🇺🇸 · Gordan Krnjaic🇺🇸 · Takuya Okawa🇺🇸

    The Standard Model of particle physics does not explain the origin of the universe's baryon asymmetry or its primordial fluctuations. The Affleck-Dine mechanism is a well-motivated scenario for generating the baryon asymmetry through the post-inflationary dynamics of a complex scalar field with baryon number. The curvaton mechanism is a popular approach for producing curvature perturbations through the dynamics of a light spectator field which decays after inflation. We demonstrate that the same complex field can viably perform both roles without any modifications to the minimal realization of Affleck-Dine baryogenesis. This scenario can also accommodate appreciable levels of primordial non-Gaussianity, beyond those achievable with only a real-valued curvaton field, and may be observable with future CMB experiments.

    hep-phastro-ph.COPRD(2026)·1 citation
18. 18*

    A Simple Parametrisation of the Pion Form Factor

    Matthew Kirk🇬🇧 · Bastian Kubis🇩🇪 · Méril Reboud🇫🇷 · Danny van Dyk🇬🇧

    We discuss a novel and simple parametrisation of the pion vector form factor that transparently connects spacelike and timelike regions of the momentum transfer $q^2$. Our parametrisation employs the framework of conformal mapping and respects the known analyticity properties of the form factor, accounting explicitly for the $\rho (770)$-meson pole. The parametrisation manifestly fulfils the normalisation condition at $q^2=0$ as well as further restrictions at the pion production threshold and in the limit $|q^2|\to \infty$. In contrast to the widely used Omnès parametrisation, our approach does not use the pion-pion scattering phase shift as input. We confront the parametrisation with experimental data from $\pi H$ scattering and ${\tau }^{-}\to {\pi }^{-}{\pi }^0\nu$ decay. We already find a good description of the data with only five free parameters, which include the pole mass and decay width of the $\rho (770)$.

    hep-phhep-exhep-latPLB(2025)·13 citations
19. 19*

    Possible $D_1{D}_1$, $D_1{\bar{D}}_1$, $B_1{B}_1$ and $B_1{\bar{B}}_1$ molecular states and the recoil corrections

    Xiao Chen🇨🇳 · Li Ma🇨🇳

    Recoil correction appears at $O(\frac{1}{M})$, which turns out to be very essential for the hadronic molecules with heavy flavor. In the past, we always thought that the recoil corrections were unfavorable to the formation of the molecular states, but our research reveals its importance to form the di-hadron bound states. In some cases, we are unable to find the bound states without considering the recoil corrections. Under SU(2) chiral symmetry, we have studied the $D_1{D}_1$, $D_1{\bar{D}}_1$, $B_1{B}_1$ and $B_1{\bar{B}}_1$ systems in the framework of the one-boson exchange (OBE) model with the treatments of the $S$\--{}$D$ wave mixing effect and the recoil corrections. Our results indicate that both the $D_1{D}_1$ system with $I(J^P)=0(1^{+})$ and $I(J^P)=1(2^{+})$ can form the molecular states whether with the recoil corrections or not, while the $D_1{D}_1$ system with $I(J^P)=1(0^{+})$ fail to form a hadronic molecule without the recoil corrections but it turns out to be a loosely bound state after the inclusion of the recoil corrections. And we have found the deuteron-like states for the $D_1{\bar{D}}_1$, $B_1{B}_1$ and $B_1{\bar{B}}_1$ systems, whether considering the recoil corrections or not.

    hep-phEPJA(2025)·3 citations
20. 20*

    Azimuthal modulation in light-by-light scattering from ultraperipheral collisions at LHC

    Yu Jia🇨🇳 · Shuo Lin🇨🇳 · Jian Zhou🇨🇳 · Ya-jin Zhou🇨🇳

    Elastic light-by-light(LbL) scattering, one of the most fascinating processes in the Standard Model(SM), has recently been observed in the ultraperipheral collisions(UPCs) of relativistic heavy ions in the Atlas and CMS experiments at the Large Hadron Collider LHC. Recognizing that the incident quasi-real photons in LbL scattering are strongly linearly polarized, we re-investigate the LbL scattering in UPCs by incorporating the joint dependence of the impact parameter and transverse momenta of the incident photons. We show that the linear polarization of incident photons generates a sizable $\cos 2\varphi$-type azimuthal modulation, which awaits the test in future LHC and EIC experiments.

    hep-phhep-exnucl-exnucl-th4 citations
21. 21*

    Machine-Learning Analysis of Radiative Decays to Dark Matter at the LHC

    Ernesto Arganda🇪🇸 · Marcela Carena🇺🇸 · Martín de los Rios🇪🇸 · Andres D. Perez🇪🇸 · Duncan Rocha🇺🇸 · Rosa M. Sandá Seoane🇪🇸 · Carlos E. M. Wagner🇺🇸

    The search for weakly interacting matter particles (WIMPs) is one of the main objectives of the High Luminosity Large Hadron Collider (HL-LHC). In this work we use Machine-Learning (ML) techniques to explore WIMP radiative decays into a Dark Matter (DM) candidate in a supersymmetric framework. The minimal supersymmetric WIMP sector includes the lightest neutralino that can provide the observed DM relic density through its co-annihilation with the second lightest neutralino and lightest chargino. Moreover, the direct DM detection cross section rates fulfill current experimental bounds and provide discovery targets for the same region of model parameters in which the radiative decay of the second lightest neutralino into a photon and the lightest neutralino is enhanced. This strongly motivates the search for radiatively decaying neutralinos which, however, suffers from strong backgrounds. We investigate the LHC reach in the search for these radiatively decaying particles by means of cut-based and ML methods and estimate its discovery potential in this well-motivated, new physics scenario. We demonstrate that using ML techniques would enable access to most of the parameter space unexplored by other searches.

    hep-phcs.LGhep-exJHEP(2025)·6 citations
22. 22*

    How large could CP violation in neutral $B$ meson mixing be? Implications for baryogenesis and upcoming searches

    Carlos Miró🇪🇸 · Miguel Escudero🇨🇭 · Miguel Nebot🇪🇸

    CP violation in neutral $B$ meson oscillations is an experimental observable that could be directly related to the baryon asymmetry of the Universe through the $B$-Mesogenesis mechanism. As this phenomenon is highly suppressed in the Standard Model, it could also be a sensitive probe for many new physics scenarios that modify neutral meson mixing. Motivated by these facts, and the timely $B$ physics program at the LHC and Belle II, we analyze how large CP violation in the mixing of neutral $B_d$ and $B_s$ meson systems could be. We answer this question, in light of current experimental data, within three different scenarios, namely: (i) generic heavy new physics only affecting the mass mixing $M_{12}^q$, (ii) vector-like quark extensions that introduce deviations of 3$\times$3 CKM unitarity, and (iii) light new physics modifying the decay mixing ${\Gamma }_{12}^q$. We find that enhancements of the semileptonic asymmetries, that measure the amount of CP violation in mixing, at the level of $10^{-3}$ for the $B_d$ system and $10^{-4}$ for the $B_s$ system can be achieved within scenarios (i) and (ii), while they are much more suppressed in realistic UV completions triggering scenario (iii). With respect to cosmology, the difficulty of finding large CP asymmetries in our analysis puts the $B$-Mesogenesis mechanism in tension. Finally, we conclude that upcoming experimental searches for CP violation in $B$ meson mixing at LHCb and Belle II are unlikely to detect a new physics signal for the most generic models.

    hep-phastro-ph.COhep-exPRD(2024)·10 citations
23. 23*

    Displaced Searches for Axion-Like Particles and Heavy Neutral Leptons at Mu3e

    Simon Knapen🇺🇸 · Toby Opferkuch🇮🇹 · Diego Redigolo🇮🇹 · Michele Tammaro🇮🇹

    We present strategies for the Mu3e experiment to search for light, weakly coupled particles produced in rare muon decays, focusing on displaced $e^{+}{e}^{-}$ decays within the hollow target. In most scenarios the backgrounds can be fully suppressed with a suitable set of cuts. We furthermore quantify the interplay between displaced and prompt searches at Mu3e and existing constraints, showing how Mu3e has a unique opportunity to probe unexplored parameter space.

    hep-phJHEP(2025)·18 citations
24. 24*

    An end-to-end generative diffusion model for heavy-ion collisions

    Jing-An Sun🇨🇳 · Li Yan🇨🇳 · Charles Gale🇨🇦 · Sangyong Jeon🇨🇦

    We train a generative diffusion model (DM) to simulate ultra-relativistic heavy-ion collisions from end to end. The model takes initial entropy density profiles as input and produces two-dimensional final particle spectra, successfully reproducing integrated and differential observables. It also captures higher-order fluctuations and correlations. These findings suggest that the generative model has successfully learned the complex relationship between initial conditions and final particle spectra for various shear viscosities, as well as the fluctuations introduced during initial entropy production and hadronization stages, providing an efficient framework for resource-intensive physical goals. The code and trained model are available at https://huggingface.co/Jing-An/DiffHIC/tree/main.

    ↳ nucl-thhep-phnucl-exPRC(2025)·10 citations
25. 25*

    Particle Acceleration Time due to Turbulence-Induced Magnetic Reconnection

    Elisabete M. de Gouveia Dal Pino🇨🇺 · Tania E. Medina-Torrejon

    We numerically investigate a crucial parameter for understanding particle acceleration theory via turbulence-induced magnetic reconnection: the particle acceleration time. We examine particles accelerated either during the jet's dynamic evolution or in a post-processing, nearly stationary regime. We derive the particle acceleration time and compare it with theoretical predictions for both the Fermi and drift regimes identified in the simulations. In the Fermi regime, the acceleration time is expected to be independent of the particles' energy, for constant reconnection velocity, as energy increases exponentially with time. Conversely, we expect the reconnection acceleration time to depend on the current sheet's thickness and the reconnection velocity, a dependence recently revisited by xu and lazarian 2023. They identified three conditions for \(t_{acc}\). We tested these relations using statistical distributions of the current sheets' thickness and reconnection velocities in the turbulent jet over time. The resulting average value of \(t_{acc}\) was found to be nearly constant with particle energy. We compared this acceleration time with the average acceleration time derived directly from 50,000 particles accelerated in situ in the same relativistic jet. When considering a longer time interval for particle acceleration in a nearly stationary snapshot of the turbulent jet, we find that the acceleration time during the Fermi regime remains nearly independent of particle energy and aligns with the acceleration time theoretical relations up to the threshold energy, attained when the particles Larmor radius becomes as large as the thickness of the largest current sheets. Beyond this threshold, the acceleration regime shifts to the slower drift regime, showing strong energy dependence, as predicted. The results also indicate a clear dominance of the Fermi regime of acceleration.

    ↳ astro-ph.HEhep-phApJ(2026)·9 citations
26. 26*

    Impact parameter dependence of the effect of background field on coupling constant in heavy ion collisions

    Cong Li🇨🇳

    We investigated the impact parameter dependence of the background field's effect on the coupling constant of the $\gamma \gamma \to l^{+}{l}^{-}\gamma$ process in heavy-ion collisions. The peripheral electric fields of heavy ions collide, and after photon annihilation into lepton pairs, the subsequent emission of radiation photons will be affected by the background field. Numerical estimates indicate that the dependence of this effect on the impact parameter is significant during this process.

    ↳ nucl-thhep-ph0 citations
27. 27*

    Observation of the Singly Cabibbo-Suppressed Decay ${\Lambda }_c^{+}\to p{\pi }^0$

    BESIII Collaboration: M. Ablikim · M. N. Achasov · P. Adlarson · O. Afedulidis · X. C. Ai · R. Aliberti · A. Amoroso · Q. An · Y. Bai · O. Bakina · I. Balossino · Y. Ban and 650 other authors

    Utilizing 4.5${\mathrm{fb}}^{-1}$ of $e^{+}{e}^{-}$ annihilation data collected with the BESIII detector at the BEPCII collider at center-of-mass energies between 4.600 and 4.699 GeV, the first observation of the singly Cabibbo-suppressed decay ${\Lambda }_c^{+}\to p{\pi }^0$ is presented, with a statistical significance of $5.4\sigma$. The ratio of the branching fractions of ${\Lambda }_c^{+}\to p{\pi }^0$ and ${\Lambda }_c^{+}\to p\eta$ is measured as $\mathcal{B}({\Lambda }_c^{+}\to p{\pi }^0)/\mathcal{B}({\Lambda }_c^{+}\to p\eta )=(0.120\pm 0.026_{stat.}\pm 0.007_{syst.})$. This result resolves the longstanding discrepancy between earlier experimental searches, providing both a decisive conclusion and valuable input for QCD-inspired theoretical models. A sophisticated deep learning approach using a Transformer-based architecture is employed to distinguish the signal from the prevalent hadronic backgrounds, complemented by thorough validation and systematic uncertainty quantification.

    ↳ hep-exhep-phPRD(2025)·13 citations
28. 28*

    Observation of a rare beta decay of the charmed baryon with a Graph Neural Network

    BESIII Collaboration: M. Ablikim · M. N. Achasov · P. Adlarson · O. Afedulidis · X. C. Ai · R. Aliberti · A. Amoroso · Q. An · Y. Bai · O. Bakina · I. Balossino · Y. Ban and 649 other authors

    The beta decay of the lightest charmed baryon ${\Lambda }_c^{+}$ provides unique insights into the fundamental mechanism of strong and electro-weak interactions, serving as a testbed for investigating non-perturbative quantum chromodynamics and constraining the Cabibbo-Kobayashi-Maskawa (CKM) matrix parameters. This article presents the first observation of the Cabibbo-suppressed decay ${\Lambda }_c^{+}\to n{e}^{+}{\nu }_e$, utilizing $4.5{\mathrm{fb}}^{-1}$ of electron-positron annihilation data collected with the BESIII detector. A novel Graph Neural Network based technique effectively separates signals from dominant backgrounds, notably ${\Lambda }_c^{+}\to \Lambda e^{+}{\nu }_e$, achieving a statistical significance exceeding $10\sigma$. The absolute branching fraction is measured to be $(3.57\pm 0.34_{stat.}\pm 0.14_{syst.})\times 10^{-3}$. For the first time, the CKM matrix element $\left|V_{cd}\right|$ is extracted via a charmed baryon decay as $0.208\pm 0.011_{exp.}\pm 0.007_{\mathrm{LQCD}}\pm 0.001_{{\tau }_{{\Lambda }_c^{+}}}$. This work highlights a new approach to further understand fundamental interactions in the charmed baryon sector, and showcases the power of modern machine learning techniques in experimental high-energy physics.

    ↳ hep-exhep-lathep-phnucl-exNature Commun.(2025)·23 citations
29. 29*

    Holographic Non-Hermitian Lattices and Junctions and their RG Flows

    Daniel Arean🇪🇸 · David Garcia-Fariña🇪🇸

    We construct and study inhomogeneous non-Hermitian strongly coupled holographic field theories. We consider two models: a lattice where in each site there is some inflow/outflow of matter and a Hermitian/non-Hermitian/Hermitian junction. By tuning a complex external gauge field, we find a non-Hermitian model which can be mapped to a Hermitian one via a complexified U(1) gauge transformation. On the other hand, in the absence of the gauge field we find non-Hermitian solutions with a purely imaginary current. Despite this, all expectation values respect PT symmetry and thus we expect the system to feature unitary time evolution. Nonetheless, we have not found a map bringing these solutions to a Hermitian description. We study the RG flows of solutions with imaginary current finding that in the IR they can be mapped to a Hermitian conformal fixed point via a complexified U(1) transformation. Remarkably, we also obtain solutions where the null energy condition is violated near the boundary of the dual geometry.

    ↳ hep-thcond-mat.str-elhep-phquant-phJHEP(2025)·4 citations
30. 30*

    Semi-Hadronic Charge-Parity Violation Interaction Constants in CsAg, FrLi and FrAg molecules

    Aurélien Marc🇫🇷 · Timo Fleig🇫🇷

    We present a systematic study of the nucleon-electron tensor-pseudotensor (Ne-TPT) interaction in candidate molecules for next-generation experimental searches for new sources of charge-parity violation. The considered molecules are all amenable to assembly from laser-cooled atoms, with the francium-silver (FrAg) molecule previously shown to be the most sensitive to the Schiff moment interaction in this set. Interelectron correlation effects are treated through relativistic general-excitation-rank configuration-interaction theory in the framework of the Dirac-Coulomb Hamiltonian. We find in FrAg the Ne-TPT interaction constant to be $W_T(\text{Fr})=2.58\pm 0.21[{⟨\Sigma ⟩}_A\mathrm{kHz}]$, considering the Francium atom as target of the measurement. Taking into account nuclear structure in a multi-source interpretation of a measured electric dipole moment, FrAg is found to be an excellent probe of physics beyond the Standard Model as this system will in addition to its sizeable Ne-TPT interaction constant greatly constrain fundamental parameters such as the quantum-chromo-dynamic $\bar{\theta }$ or the semileptonic four-fermion interaction $C_{lequ}$ from which nuclear and atomic $\mathcal{C}\mathcal{P}$-violating properties arise.

    ↳ physics.atom-phhep-phquant-phEur.Phys.J.D(2025)·3 citations
31. 31*

    Observation of string-breaking dynamics in a quantum simulator

    Arinjoy De🇺🇸 · Alessio Lerose🇬🇧 · De Luo🇺🇸 · Federica M. Surace🇺🇸 · Alexander Schuckert🇺🇸 · Elizabeth R. Bennewitz🇺🇸 · Brayden Ware🇺🇸 · William Morong🇺🇸 · Kate S. Collins🇺🇸 · Zohreh Davoudi🇺🇸 · Alexey V. Gorshkov🇺🇸 · Or Katz🇺🇸 · Christopher Monroe🇺🇸

    Spontaneous particle-pair formation is a fundamental phenomenon in nature. It can, for example, appear when the potential energy between two particles increases with separation, as if they were connected by a tense string. Beyond a critical separation, new particle pairs can form, causing the string to break. String-breaking dynamics in quantum chromodynamics play a vital role in high-energy particle collisions and early universe evolution. Simulating string evolution and hadron formation is, therefore, a grand challenge in modern physics. Quantum simulators, well-suited for studying dynamics, are expected to outperform classical computing methods. However, the required experimental capabilities to simulate string-breaking dynamics have not yet been demonstrated, even for simpler models of the strong force. We experimentally probe, for the first time, the spatiotemporal dynamics of string-breaking in a (1+1)-dimensional ${\mathbb{Z}}_2$ lattice gauge theory using a fully programmable trapped-ion quantum simulator. We emulate external static charges and strings via site-dependent magnetic-field control enabled by a dual array of tightly focused laser beams targeting individual ions. First, we study how confinement affects isolated charges, finding that they freely spread without string tension but exhibit localized oscillations when tension is increased. Then, we observe and characterize string-breaking dynamics of a string stretched between two static charges after an abrupt increase in string tension. Charge pairs appear near the string edges and spread into the bulk, revealing a route to dynamical string-breaking distinct from the conventional Schwinger mechanism. Our work demonstrates that analog quantum simulators have achieved the necessary control to explore string-breaking dynamics, which may ultimately be relevant to nuclear and high-energy physics.

    ↳ quant-phcond-mat.quant-gashep-lathep-ph+1100 citations
32. 32*

    Tensor Integrals in the Large-Scale Structure

    Hayden Lee🇺🇸

    We present a new method for evaluating tensor integrals in the large-scale structure. Decomposing a $\Lambda$CDM-like universe into a finite sum of scaling universes using the FFTLog, we can recast loop integrals for biased tracers in the large-scale structure as certain tensor integrals in quantum field theory. While rotational symmetry is spontaneously broken by the fixed reference frame in which biased tracers are observed, the tensor structures can still be organized to respect the underlying symmetry. Projecting the loop integrands for scaling universes onto spherical harmonics, the problem effectively reduces to the evaluation of one-dimensional radial integrals, which can be solved analytically. Using this method, we derive analytic expressions for the one-loop power spectrum, bispectrum, and trispectrum for arbitrary multipole moments in the basis of scaling universes.

    ↳ astro-ph.COhep-phhep-th4 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.